[Role of sympathetic innervation of the upper respiratory tract in the reflex effects of its mechanoreceptors].

In anesthetized cats, stimulation of the mechanoreceptors of the pharynx, under--and subfold spaces of the larynx, and trachea evoked electrical responses in the peripheral and central parts of the cervical sympathetic nerve. Bilateral transection of the cervical sympathetic nerves diminished the respiratory and vasomotor reflexes from the mechanoreceptors. The signals from the receptors of the upper respiratory tract seem to reach the c. n. s. not only by the vagal fibers but the sympathetic afferent fibers as well. The reflex influences from the receptors of the upper respiratory tract on the respiratory and cardiovascular systems and on the upper respiratory tract itself are realized both by vagal and the sympathetic ways.